Firearm comprising counter recoil device

ABSTRACT

The invention relates to firearms and especially shotguns as well as devices or mechanisms for reducing felt recoil. In particular, the invention relates to a gas-operated device to reduce felt recoil using a recoil suppressing mass, or recoil mass, to create a counter-acting force to the recoil force. The recoil mass moves in response to the gas pressure in the barrel after firing, and more particularly the control of the flow of gas into a chamber to force the recoil mass to move and generate a recoil suppressing force. In one aspect, incorporating the gas-operated device in a firearm can improve the operator&#39;s control of the firearm and measurably reduces felt recoil and/or muzzle climb

REFERENCE TO RELATED APPLICATIONS

This application claims priority benefit of U.S. provisional application61/025,608, filed Feb. 1, 2008, the entire contents of which areincorporated herein by reference.

FIELD OF INVENTION

The invention relates to firearms and especially shotguns as well asdevices or mechanisms for reducing felt recoil. In particular, theinvention relates to a gas-operated device to reduce felt recoil using arecoil suppressing mass, or recoil mass, to create a counter-actingforce to the recoil force. The recoil mass moves in response to the gaspressure in the barrel after firing, and more particularly the controlof the flow of gas into a chamber to force the recoil mass to move andgenerate a recoil suppressing force. In a shotgun, and especially asemi-automatic or automatic shotgun, the recoil forces are notoriouslyhigh and the incorporation of the devices of the invention can providedramatic improvement to the safe or efficient handling of a firearm. Inone aspect, incorporating the gas-operated device in a firearm canimprove the operator's control of the firearm and measurably reducesfelt recoil and/or muzzle climb.

BACKGROUND FOR AND INTRODUCTION TO THE INVENTION

The operating mechanisms found on current firearms, although reliableand widely employed, nevertheless suffer from a number of deficiencies.The recoil forces generated with some firearms essentially renders themunsatisfactory from an accuracy and muzzle climb perspective. Notableexamples of rifles that cannot be controlled in automatic mode ascompared to semi-automatic mode exist.

For shotguns in particular, a gas pressure loader for semi-automaticoperation has been used for some time. These semi-automatic shotgunsgenerally require a defined gas pressure and an easily removable, ruggedcartridge shell. With modern, powerful cartridges that are metal with along sleeve and a shell body made of plastic, the gas pressure loadershotguns enjoy relatively trouble-free operation. However, the recoilforces generated by shotguns is typically quite high even in thesemi-automatic mode.

In general and in one aspect, the invention addresses the design offirearms by providing a new gas pressure operated device to generate acounter-acting force that acts to suppress at least part of the recoilforces generated upon firing.

SUMMARY OF THE INVENTION

The present invention addresses the problems and disadvantagesassociated with conventional firearms and weapon systems and providesimproved devices for reducing recoil effects in a variety of firearms.

In one particular embodiment of the present invention, a recoil controldevice for use in a firearm comprises a bolt configured to alternatebetween a forward position and a rearward position in response to thefiring of one or more cartridges. The firearm includes a barrel and acounter recoil assembly having a recoil mass chamber and recoil mass.The barrel comprises a first gas port capable of transmitting orcommunicating gas from the barrel into a recoil mass chamber, where therecoil mass chamber has an internal moving recoil mass that moves inreaction to gas pressure communicated from the barrel. The barrel mayalso comprise a second gas port in communication with an action pistontube, optionally through a gas manifold, the tube having an actionpiston and a bolt carriage rod linked to the bolt assembly to move thebolt from a forward position to a rearward position in reaction to gaspressure in the barrel. Through these components the firing of thefirearm creates a counter recoil force generated by the movement of therecoil mass in response to gas pressure through the first gas port. Thecounter recoil force actually suppresses the felt recoil and can reducemuzzle climb and can improve the handling of the firearm. While apreferred arrangement of the recoil mass chamber places it near thebarrel, as shown in the Drawings, another preferred arrangement placesthe recoil mass chamber in or at least partially within the stock of thefirearm. In this and any embodiment of the invention, the first gas portfrom the barrel can transmit gas pressure to a recoil mass chamberthrough one or more tubes, a gas manifold or gas block, a system oftubes, or other means of gas communication. As referred to here andthroughout this disclosure, a first gas port can refer not only to asingle gas port in the barrel, but multiple gas ports located atessentially the same position on the length of the barrel. Thus, thefirst gas port can refer to the relative timing of the gas pressureentering the first gas port or transmitted from the gas port as comparedto the timing of the gas pressure entering or being transmitted from asecond gas port, if a second gas port is used. As described below, thearrangement, number, size, shape, and exit angle of the gas port(s) usedin any embodiment can be varied and the depictions in the Figures aremerely exemplary of the gas ports and gas manifolds or gas blocks thatcan be used or located on a firearm. Combinations of shapes and sizesand exit angles of gas ports can also be used in a single firearmdesign.

In a more specific embodiment of the invention described above, asemi-automatic or automatic shotgun can be designed according to theinvention. In this aspect, the firearm or shotgun comprises a barrelhaving an internal bore with a breech at its rearward end and having oneor more gas ports at a location along the bore, the gas port incommunication with a gas manifold. As in conventional shotguns intowhich the invention can be adapted, the shotgun can include a receiverhaving a stock section and a cartridge chambering section, as well as anejection port and a feed tube. In an optional embodiment of a shotgun,the invention includes a stock loading feed tube or magazine. Theshotgun can use conventional gas-operated bolt assemblies, such as onehaving at least one action piston tube in communication with a gasmanifold, or other source of pressurized gas from the barrel, and a rodassembly extending from an action piston in the action piston tube, therod operably driven by the action piston to move the bolt assembly inthe rearward direction, and a return spring to move the bolt assembly inthe forward direction to load a successive round. Generally, the boltand carriage assembly has a guide or track region supporting a movingbolt, and the bolt and carriage assembly define a cartridge receivingspace on the receiver. A rotating bolt face can be used to engage thecartridge and the bolt face may have an aperture for a firing pin, thebolt face rotating during the backward and forward movement of the boltassembly. In this or any aspect of the invention, the recoil masschamber is in communication with the above-mentioned gas manifold andthe chamber can be positioned along the barrel or parallel to thebarrel, although other arrangements are possible. This recoil masschamber contains and controls the movement of a recoil mass, whichmoves, typically but not limited to a rearward movement toward thechambering end of the barrel, in response to gas pressure in the barrelafter firing. The counter forces generated by the movement of the recoilmass suppress the felt recoil forces in response to the impulse fromfiring the firearm. Incorporating the moving recoil mass incommunication with the pressurized gas transmitted from the barrel inthis way advantageously uses the energy from firing each round toimprove the performance of a firearm.

In any firearm or shotgun embodiment of the invention, the gas pressureutilized in a gas manifold, gas communication tubes or gas connector ortransmission tubes, or other tubes or conduits for transmitting gaspressure from the barrel as described throughout this disclosure, can beoptionally regulated. Various gauges, bleed ports, vents, regulators,valves, or tube design or construction options are available forregulating the pressure and even the timing of the gas transmission.

In any firearm or shotgun embodiment of the invention, an electronictrigger and firing system can optionally be used, including a trigger, abattery or power supply, a mechanical switch actuated by an electricalsignal from the trigger to actuate the movement of a firing pin, and afiring pin. Conventional mechanically driven firing pins linked to atrigger, sear, and hammer as used in various other firearms can also beused. The choice of the firing mechanism and its parts is not especiallyimportant in making and using the counter recoil systems and apparatusof the invention.

In any embodiment of the invention, the path of the recoil mass inresponse to the impulse from gas pressure can be varied from that shownin the drawings. The recoil mass can move along a path defined by itschamber, which may include internal tracks, rollers, or guides. Thus, astraight path toward the anterior of the firearm, a curved orcurvi-linear path, a path extending outward from the barrel, a pathmoving inward toward the barrel, and a path crossing over the barrel canpossibly be selected. Furthermore, multiple recoil masses in multiplechambers can be used if desired. The path chosen and the recoil massshape and design relates to the design characteristics of a particularfirearm. The recoil forces can be further controlled or managed throughthe positioning of the barrel of the firearm relative to the grip orstock of the weapon. While not depicted in the drawings, embodimentswith more than one recoil mass within one recoil mass chamber can alsobe used. Combinations of recoil mass chambers and recoil mass designsand numbers with multiple chambers for each barrel are also possible.

In any embodiment of the invention, the recoil mass chamber can be aclosed or sealed tube except for the input of pressurized gastransmitted or communicated from the barrel and a pressure release orbleed valve. The bleed valve can be adjustable or regulated by the userin order to optimize the performance of the firearm, and one or moregauges to monitor gas pressure or peak gas pressure at various pointscan be incorporated into the system. The bleed valve allows the pressurein the recoil mass chamber to be released during the action of thefirearm. The location of the bleed valve is not critical, but it mayoptionally be placed at the rearward end or back of the gun end of thechamber. Similarly, the action piston tube can be a closed or sealedtube except for the input of pressurized gas and a pressure release orbleed valve. The pressure release or bleed valve can be regulated oradjusted by the user and again one or more gauges can be incorporatedfor this purpose. Again, the position of the bleed valve in the actionpiston tube is not critical, but it can be located at the rearward end.

The devices, mechanisms and aspects of the invention can be used tocomplement or improve existing or conventional firearms and can becombined with various arrangements, attachments, and combinations,including without limitation internal lock and release systems, loadingsystems, ejection systems, gas injection systems, recoil reduction stockdevices and systems, muzzle brakes, directional barrel ports, sightingsystems, tripods, mounting systems, and firing mechanisms.

In one general aspect, the invention comprises a counter recoil devicethat employs the gas pressure from the barrel to create a counter recoilforce by generating the sudden movement of one or more recoil masses.Generally, as noted above, the recoil mass or masses are confined withinone or more closed chamber or chambers, but other configurations withpartially closed chambers can be used. The counter recoil force isgenerally timed to reduce the total felt recoil forces, as can be seenin the graph of FIG. 5. While time periods immediately after or as soonas possible after the percussion or initial impulse from firing may bedesired, other time periods for generating the counter recoil forces canbe selected. Optionally, recoil mass movement within about 0.0005seconds, or about 0.0025 seconds, or about 0.005 seconds from thedetection of the initial filing impulse as felt recoil (see FIG. 5) ispreferred in order to reduce recoil levels substantially. Furthermore,multiple recoil masses can generate counter forces simultaneously oreven at different time points compared to the initial impulse of firing.Accordingly, the reduction in felt recoil predicted by FIG. 5 can beexceeded in certain designs to provide 50%, 60%, 70%, 80%, or even 90%reduction in felt recoil. While no specific level of felt recoilreduction is required, it is generally understood that about 20% or morereduction in felt recoil can be generated by the use of the suppressiverecoil force provided by the invention.

The recoil suppression device can be manifested as in one of the Figuresaccompanying this disclosure. Also, numerous embodiments andalternatives are disclosed in the accompanying claims. In anotheraspect, the invention provides a method for making a counter recoildevice of the invention and/or incorporating into a firearm a counterrecoil device comprising one or more recoil masses as described here.

Other embodiments and advantages of the invention are set forth in partin the description that follows, and in part, will be obvious from thisdescription, or may be learned from the practice of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the invention and some advantagesthereof, reference is now made to the following descriptions taken inconnection with the accompanying drawings in which

FIG. 1 is a side view of an exemplary shotgun of the invention, wherethe dotted lines indicate internal elements.

FIG. 2 depicts a frontal view of an exemplary shotgun, looking into thebarrel.

FIGS. 3 a-d depict the movement of particular parts and the counterrecoil device during the operation of an exemplary firearm.

FIG. 4 depicts specific elements of an exemplary counter recoil deviceof the invention.

FIG. 5 shows a graph of the recoil forces (Force v Time) from asimulated firing of a shotgun cartridge using the counter recoil deviceof the invention.

FIG. 6 depicts a schematic side view of various elements of an exemplarycounter recoil system or device of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The incorporation of the novel recoil controlling device of theinvention onto a rifle, firearm, and particularly a shotgun candramatically reduce felt recoil and/or muzzle climb during operation.Especially with semi-automatic and automatic firing modes, muzzle climbcan adversely effect accuracy in firing. In the testing of an exemplaryembodiment, the use of the counter-acting recoil device results in about37-40% reduction of felt recoil as calculated at the shoulder of ahypothetical operator as compared to firing when the counter-actingrecoil system is not operating. Further data can be expressed as degreesof muzzle climb measured in a standard Ransom International (Prescott,Ariz.) firearm rest versus time under similar conditions for a firearm.

As discussed, one preferred embodiment of the invention is a shotgunincorporating a counter recoil force-generating device, as generallydepicted in FIG. 1, where the bolt assembly (110) is in line with thebarrel (100). Charging handle (116) connected to bolt assembly is usedto cock firearm and can optionally incorporate a folding externalhandle. A recoil suppressive mass chamber (190) can be positioneddirectly below the barrel (100). One or more gas port blocks at (150) ormanifolds in the barrel are in communication with a gas manifold (154)that directs the pressurized gas from the barrel (100) into the recoilmass chamber (190). A threaded assembly knob (140) can be used todisassemble the firearm, as in conventional shotguns. A preferred designincorporates a magazine or feed tube in the stock as shown at (130).

FIG. 2 shows a front view of the shotgun in FIG. 1, where charginghandle (116), barrel (100), recoil suppressive mass chamber (190), andbolt carriage piston tube (170) are shown in relation to each other.

FIGS. 3 a-3 d depict the operation of the recoil suppressive mass (160)in a firearm. In FIG. 3 a, the recoil mass (160) is at its restingposition at forward end of the chamber (190). The recoil spring (192) inchamber (190) is depicted in FIG. 3 a but not shown in other views. Thecartridge (120) is in a cocked and loaded position with casing ofcartridge (121) against bolt face (114). Bolt assembly (110)incorporates a firing pin as in conventional firearms, but optionally,as discussed below, employs an electronic control of the movement of thefiring pin (not shown here). A first gas port block (150) having one ormore gas ports (158) from the barrel (100) into the gas block (150) isat a first position, near rearward end of barrel (100). One or more gasconnector tubes (152) connect first gas block (150) to gas manifold(154). Gas manifold (154) can be an integrated part, as shown here, tohold chamber (190) by its circular region and connect it to barrel (100)by welded connection, for example. Conventional bolt carriage system,with tube (170), rod (180) and piston (172) that move in response to gaspressure to release bolt assembly and push it rearward are alsoincorporated. At forward end of chamber (190) is an optional recoil massbuffer (162) to reduce impact force of recoil mass (160) in its returnmovement pushed by recoil spring (192). The buffer can itself be aspring, an elastic material, or a fluidic system using chambers toabsorb the impact force of the recoil mass.

The gas ports defined in the barrel are depicted in the drawings asessentially perpendicular to the linear axis of the barrel. However,embodiments where the direction of the gas ports are angled as comparedto this perpendicular arrangement or where a port is beveled can bepreferred. Furthermore, the size and shape of any of the gas ports usedor depicted is not fixed to the circular or oval ports specificallyshown. The size, shape, number of gas ports, and the direction of one ofmore of the gas ports or tubes can be varied for a number of reasons,including preventing the clogging or spoiling of gas flow. Similarly,gas ports are shown at the lower surface of the interior bore of thebarrel in the drawings, but there is no requirement that they be placedexclusively at that position.

In FIG. 3 b the projectile of cartridge, represented as cylinder (120),has moved through barrel (100) in response to firing. Gas pressure inbarrel (100) moves through gas port (158) and through gas manifold (154)in communication with recoil mass chamber (190) to force movement inrearward direction (210) of recoil mass (160). The counter recoilsuppressive force represented by (200) is generated in reaction to themovement of the recoil mass (160). The recoil mass and other operatingparts can be composed of metal, such as steel or aluminum, or of otheror heavier materials such as tungsten or titanium. The weight of therecoil mass (160) can be varied depending on the size of the cartridgeintended. For a 12-gauge shotgun with 28 inch barrel, for example, arecoil mass weight of about 0.5 lbs (about 225 grams) or about 0.4 lbs(about 180 grams) can be used. Of course, various shotgun barrellengths, such as the general range between 26-30 inches, can beselected. Furthermore, the bolt assembly can be selected from the sizesand weights generally used or available in the field, such as a weightof approximately 0.7 lbs (about 320 grams). As shown in the chart ofFIG. 5 calculated from an exemplary, hypothetical shotgun and operatoras discussed here, the suppressive counter-acting force can result in anear instantaneous reduction in recoil at a point near the initialimpulse (about 0.0025 secs in FIG. 5), to dramatically reduce the feltrecoil forces for a period of time. The total felt recoil force for acalculation as shown in FIG. 5 is typically represented by the areaunder the curve, and the operation of the counter-acting recoil mass andthe suppressive force it generates reduces that area significantly (seearrow in FIG. 5).

In FIG. 3 c the projectile (120) has moved past one or more gas port(156) in manifold (154) to allow pressurized gas to force movement inrearward direction (220) of action piston (172) in tube (170). Movementof piston (172) pushes rod (180) to begin rearward movement of boltassembly (110) to release spent cartridge from bolt face (114). Therecoil mass is further along in its movement in the chamber (190),although the placement of recoil mass (160) and piston (172) isestimated in these figures.

In FIG. 3 d the projectile has left the barrel (100) and recoil mass(160) is at or near rearward point and/or beginning forward movementpushed by recoil spring or other elastic device (not shown). Piston(172) generally does not travel the full extent of tube (170) and hereis shown at approximate rearward point to force bolt assembly (110)back. Gap in area between end of barrel (100) and bolt face (114) allowsrotating bolt face (114) and ejector (not shown) to release spentcartridge shell (121). Direction that spent cartridge is ejected can becontrolled by design choices according to devices and technologyavailable in the art. Thus, upward, downward, or left/right directionalejection or the ability to change the direction for left or right handedoperators can be used and incorporated into a firearm as discussed hereand known in the art.

After spent cartridge is ejected, return spring moves bolt carriageassembly forward and bolt face (114) catches next cartridge advancinginto a loading position from magazine or feed tube (not shown). Inoptional embodiments, a lock system is used to prevent the nextcartridge from moving into a loading position unless the bolt assemblyis in proper placement. After the next cartridge is advanced and movedinto position on the bolt face, the bolt assembly continues forward andlocks into the firing or loaded position.

FIG. 4 depicts an exemplary recoil mass system that can be incorporatedinto a firearm where the elements are as described above. Here, a firstgas port (158) set of ports allows pressurized gas to be incommunication with gas manifold (154) through tubes (152) also referredto as connector tubes. Gas manifold (154) can be used to both connectchamber (not shown) to barrel (not shown) and to direct pressurized gasin various directions. Gas flow tubes (155) internal to gas manifold canregulate the amount of gas that is directed into recoil mass chamber andtherefore to control amount of force that acts on recoil mass. Anexternal, operator-controlled regulator can be incorporated into themanifold design to allow the operator to adjust flow of gas intochamber, thereby controlling the counter-acting force generated bymovement of recoil mass. This as well as other regulators can thereforebe used to bleed some part of the gas pressure out of the system duringoperation. Use of a regulator can advantageously adjust the firearm fordifferent shotgun cartridges and the impulses different cartridges maygenerate.

FIG. 6 shows another side view of an exemplary counter recoil or recoilsuppressing device of the invention in a more schematic or idealizedpresentation. In this view, internal aspects of an exemplary boltassembly, gas manifold and gas communication system, and recoil masschamber can be seen. Parts are labeled as in the previous drawings. InFIG. 6, the firing pin (161) can be seen internal to bolt assembly(110), and external elements of bolt face (114) are more pronounced.Additional elements (163) visible in bolt assembly (110) can link withrod or action piston not shown in this view. Optional side bleed ports(164) in gas manifold (154) can be used to reduce gas pressuredistributed by manifold, but optional regulator to control externalbleed of gas pressure is not depicted. Similar to the operationdescribed above, the flow of pressurized gas from port (158) throughtube (152) and manifold (154) allows initial space in chamber (190) tofill with gas and thereby force movement of recoil mass (160). Spring(192) returns recoil mass (160) to its forward position. Here the spring(192) is shown to encompass the entire chamber (190), but other springarrangements, and indeed other return devices that are not springs, canbe selected and used. The size of the initial space at forward end ofchamber (190), here shown in opposite direction of that shown in FIGS. 3a-3 d, can be selected from various determined sizes for a particularfirearm. Here the gap is essentially below the internal gas flow tubes(155) visible in manifold (154) and is relatively small. Theconfiguration of the gap area can also be changed from the simplecylinder shown here. The placement and extent of the buffer device (162)can be seen in this side view.

The buffer device or shock absorbers incorporated can be one of manyavailable in the art, including elastomer buffers. For example, a pistonor rod can penetrate an elastomer buffer to reduce the forces on impact.A flange can be incorporated on the rod or piston to prevent the rod orpiston from slipping or form moving beyond a desired point. An elastomerbuffer can be made of several ring elements and the control of theforces can accordingly be determined by the selection of the ringelements. For example, if a relatively weak cartridge is fired, the ringelements of elastomer buffer are only partially or slightly compressed.When a strong cartridge is fired, then multiple ring elements ofelastomer buffer are compressed. Alternatively, fluidic buffersemploying a piston and chambers filled with viscous fluid can be used totemper the forces at impact. Fluidic devices are available in the artand any available device can be selected and used.

Terms such as “forward”, “rearward”, “under,” “over,” “in front of,”“the back of the gun,” or “behind,” “anterior,” “posterior,” “downward,”“upward,” or “transverse,” are used here as somebody firing a gun wouldunderstand and perceive them, which is by reference to the linear orfiring axis of the barrel when the gun is held in the usual horizontalattitude. Furthermore, “firearm” as used here encompasses shotguns,rifles, handguns, pistols, heavy caliber guns, sniper rifles, firearmswith automatic and semiautomatic action, mountable and portable cannons,firearms or cannons mounted on aircraft or naval vessels, multiplebarrel firearms, firearms or cannons mounted on armored personnelcarriers or other armored vehicles, and machine guns or cannons mountedon armored or non-armored vehicles or vessels.

Recoil mass chambers as shown and described here need not be positionedin parallel with the barrel, but can be tilted up or down to furtheradjust the counter-acting and recoil suppressive forces generated.Similarly, the movement of the recoil mass need not be parallel to thelinear axis of the barrel. While not depicted in the drawings,embodiments where the recoil mass moves in a tilted or curved path withrespect to the barrel can be employed.

In any embodiment, the gas manifold or gas connector tubes used caninclude a pressure equalizing, bleed, or exhaust port or valve in orderto reset the pressure in the recoil chamber, and/or action tube, priorto the next firing of the firearm. As noted above, the recoil masschamber and the action piston tube can themselves include a pressurerelease valve or gauge or exhaust port, and combinations of exhaustports or bleed gauges or valves can be used on the one or moremanifolds, one of more connector tubes, and/or one or more chambers ortubes. Furthermore, the recoil return device need not be a spring, butcan be any elastic or similar device or composition. A buffer or fluidicbuffer system known in the art can be used at both ends of the recoilmass chamber if desired, and can also be used at one or both ends of theaction piston tube.

The positioning of the barrel of the weapon relative to the grip orstock of the weapon can effectively allow one to manage part of therecoil moment or force component. Optionally, this invention canincorporate different placement positions of the barrel relative to theheight of a grip or the stock, such as at about 5% to about 95% of theheight of the grip or stock, or about 40% to about 80%, or about 50% toabout 70%, or about 60% to about 70%. As stated herein, any particularconfiguration of the linear axis of the barrel relative to the grip orstock can be selected.

In one particular embodiment as shown in FIGS. 1, 2, and 3 a forexample, the invention comprises a mobile bolt assembly made up ofconnected parts that comprise a bolt carriage body (110), a rotatingbolt face (114), and a carriage track or guide. The action piston (180),which moves in response to gas pressure, pushes the bolt rearward.Shotguns with similar gas-operated systems are known and available toone of skill in the art, and the invention is not limited by theselection of a particular bolt assembly or bolt design or movement.

As explained for the embodiments of the drawings, however, the rearwardmovement of the action piston drives the rod assembly rearward causingthe rod, or optionally rods located at various points, to drive the bolthousing rearward. The bolt carriage or assembly (110) can be moved backeither by hand through the charging lever (116) or automatically. Thebolt carriage generally travels a straight-line path of motion in thedepicted embodiments, but may have other desired paths. Longitudinalgrooves or tracks or incorporated rollers in the receiver (not shown)guide the bolt carriage, together with the bolt return spring and actionpiston.

Generally, the bolt or bolt assembly cannot be moved alone. The movementdistance of the bolt assembly is longer than the length of a cartridge(120+121). The bolt face (114) can be penetrated by a locking lever orhook (not shown).

To load and fire the next round, the bolt carriage (110) returns to thefront position, at the end of which the bolt face (114) contacts therearward or breech end of the barrel (100). To lock the bolt or boltface against the breech, the rotating bolt face can have locking cams orsurfaces to engage receiver as it moves forward and rotates. Anadditional locking element or projection can release a tilting lever tolock the bolt face or bolt carriage from another point along thereceiver. The firing pin is in active mode once the bolt is locked inthe breech.

It may be desirable to design the cartridge ejection system for adesired direction, except at the reloading mechanism. For example, if acartridge gripping device is positioned above the cartridge loadingchamber, then the ejection can take place to the right or to the left,or even below, depending on where a cartridge case or spent shell portcan be placed. From the foregoing, persons of ordinary skill in the artwill appreciate that improved cartridge ejection devices andarrangements have been disclosed and are available. For instance, astationary ejector can operate with one or two cartridge extractor hookssuch that, when the bolt carriage moves rearward, the cartridge orcartridge shell is extracted from the bolt face by extractor hooksmoving into contact a position. Then, the base of the cartridge shellstrikes the stationary ejector and the shell is ejected.

One skilled in the art can devise and create numerous other examplesaccording to this invention. Examples may also incorporate additionalfirearm elements known in the art, including muzzle brake, multiplebarrels, blow sensor, barrel temperature probe, electronic firingcontrol, mechanical firing control, electromagnetic firing control, andtargeting system, for example. One skilled in the art is familiar withtechniques and devices for incorporating the invention into a variety offirearm examples, with or without additional firearm elements know inthe art, and designing firearms that take advantage of the improvedforce distribution and recoil reduction characteristics of theinvention.

1. A firearm comprising: a barrel; a bolt assembly having a forwardposition and a rearward position; an action piston tube having an actionpiston; and a counter recoil assembly having a recoil mass chamber andrecoil mass, wherein the barrel comprises a first gas port incommunication with the recoil mass chamber, the recoil mass chamberhaving an internal moving recoil mass that moves in reaction to gaspressure in the barrel and independent of the bolt assembly, the firstgas port configured to delay the gas flow into the recoil mass chamberto cause the movement of the recoil mass at about 0.0025 to about 0.005seconds from firing, and wherein the barrel comprises a second gas portin communication with an action piston tube having an action piston anda bolt carriage rod linked to the bolt assembly to move the bolt from aforward position to a rearward position in reaction to gas pressure inthe barrel, whereby the firing of the firearm creates a counter recoilforce generated by the movement of the recoil mass in response to gaspressure through the first gas port.
 2. The firearm of claim 1, whereinthe firearm is a gas-operated shotgun.
 3. The firearm of claim 1 or 2,wherein the recoil mass tube is positioned below the barrel andcomprises an internal return spring at a rearward position and a bufferdevice at the forward position.
 4. The firearm of claim 1 or 2, whereinthe first gas port is in communication with a gas manifold that directsgas pressure into the recoil mass chamber.
 5. The firearm of claim 4,wherein the gas manifold has an adjustable valve for controlling thepressure directed into the recoil mass chamber or the action pistontube.
 6. The firearm of claim 1 or 2, wherein the bolt assemblycomprises a rotating bolt face region to contact a cartridge, a boltcarriage track, and a main bolt carriage body linked to the boltcarriage rod and capable of moving on the bolt carriage track from aforward, locked position to a rearward position.
 7. The firearm of claim3, wherein the buffer device comprises fluidic chambers that dampen theforce of the recoil mass as it returns to a forward position.
 8. Thefirearm of claim 1 or 2, wherein a firing system incorporated into thebolt assembly is actuated by an electronic signal initiated by a triggerthat activates a solenoid and spring to move the firing pin and contacta primer on a loaded cartridge.
 9. A semi-automatic or automatic shotguncomprising: (a) a barrel having a bore with a breech at its rearward endand the barrel having gas ports at a location along the borecommunicating with a gas manifold; (b) a receiver having an ejectionport and a feed tube; (c) at least one action piston tube incommunication with the gas manifold and a rod assembly extending from anaction piston in the tube and along the barrel, the rod operably drivenby the action piston to move a bolt assembly in the rearward directionand a return spring to move the bolt assembly in the forward direction;(d) a bolt and carriage assembly having a guide supporting a movingbolt, the bolt and carriage assembly defining a cartridge receivingspace; (e) a rotating bolt face to engage the cartridge and having anaperture for a firing pin, the face rotating during the backward andforward movement of the bolt assembly; and (f) a recoil mass chamber incommunication with the gas manifold and along the barrel, the chamberhaving a recoil mass that moves rearward in response to gas pressure inthe barrel after firing, the gas manifold configured to delay the gasflow into the recoil mass chamber to cause the movement of the recoilmass at about 0.0025 to about 0.005 seconds from firing.
 10. The shotgunof claim 9, further comprising an electronic trigger assembly includinga trigger, a power supply, a mechanical switch actuated by an electricalsignal from the trigger to actuate the movement of a firing pin.
 11. Theshotgun of claim 9 or 10, wherein the feed tube conveys cartridges byspring force in sequence into an advance position across the bolt faceduring its forward motion, and optionally a lock which holds a cartridgefrom moving into position across the bolt face.
 12. The firearm of claim1, wherein the felt recoil is reduced by the action of the recoil massby about 20% or more compared to a firearm where the recoil mass doesnot move.
 13. The firearm or shotgun of one of claim 1 or 9, wherein thefelt recoil is reduced by the action of the recoil mass by about 20% ormore compared to a firearm where the recoil mass does not move.
 14. Thefirearm or shotgun of one of claim 1 or 9, wherein the felt recoil isreduced by the action of the recoil mass by about 30% or more comparedto a firearm where the recoil mass does not move.
 15. The firearm orshotgun of one of claim 1 or 9, wherein the felt recoil is reduced bythe action of the recoil mass by about 40% or more compared to a firearmwhere the recoil mass does not move.
 16. The shotgun of claim 9, whereinthe recoil mass chamber comprises a buffer device to reduce the impactof the movement of the recoil mass.
 17. The shotgun of claim 9, whereinthe gas manifold has an adjustable valve for controlling the pressuredirected into the recoil mass chamber or the action piston tube.
 18. Theshotgun of claim 9, wherein two action piston tubes are in communicationwith the gas manifold.
 19. The shotgun of claim 18, wherein two actionpiston tubes are positioned on either side of the barrel.
 20. Theshotgun of claim 9, wherein the recoil mass chamber is below the barrel.21. The firearm or shotgun of one of claim 1 or 9, wherein the design ofthe gas flow into the recoil mass chamber causes the recoil mass to movewithin about 0.0025 seconds from initial detection of firing impulse.22. (canceled)